Mucosal erosions in the walls of the GI tract, typically referred to as ulcers or peptic ulcers, are a painful disease of the GI tract. Ulcers may occur in the stomach, doudenum and esophagus, etc.
Ulcers may be diagnosed based on characteristic symptoms such as abdominal pain, or using tests such as endoscopies or barium contrast x-rays. For example, gastroscopy may provide direct visual identification of the ulcer, including information relating to the location and severity of the ulcer. Alternatively, a swallowable in-vivo device, such as the PillCam® capsule endoscopy system commercially available from the common assignee of the present invention or an autonomous swallowable imaging device similar to embodiments described in U.S. Pat. No. 7,009,634 and/or in U.S. Pat. No. 5,604,531, each of which are assigned to the common assignee of the present invention and each of which are hereby incorporated by reference in their entirety, may travel along the GI tract, capture images of the GI tract, and send these images to a personal computer or workstation or portable recorder to be analyzed and presented to a healthcare professional. The healthcare professional may diagnose the presence of ulcers based on the captured images.
A capsule endoscope video may comprise of tens of thousands of images captured during the capsule's several hours' long passage through the GI tract. Often time, the vast majority of images in such image stream are of healthy tissue and a much smaller number of images show pathological tissue, such that the reviewer may need a long time to locate images of diagnostic interest. An automatic detection of images showing pathological tissue, such as an ulcer, may save reviewing time and increase the likelihood of detection of such pathological tissue by the reviewer.
Ulcers in the GI tract may have unique visual appearance. Typically, peptic ulcers are characterized by a white-yellowish center surrounded by a reddish halo.